iPhone 18 Pro Max underwater photography test: AquaExposure score of 4.1/5. Featuring variable aperture, ProRes RAW capabilities, confirmed Divevolk SeaTouch.
Direct Answer: The iPhone 18 Pro Max receives an AquaExposure score of 4.1/5 for underwater photography. Its variable aperture main lens (f/1.48 to f/4.0) offers real creative control over depth of field in natural light. Compatible with the Divevolk SeaTouch 6 Pro touchscreen housing for depths up to 60 meters, it nevertheless requires a strict anti-condensation protocol in cold water below 15°C.
Every year, the question arises: does the new generation of iPhone Pro Max truly change anything for underwater photography, or is it a marginal refinement disguised as a novelty?
This time, the key improvement lies in one word: aperture. The iPhone 18 Pro Max is the first iPhone to offer a variable aperture on its main sensor, ranging from f/1.48 to f/4.0, and controllable manually. On paper, this is a real compositional tool, not just a marketing gimmick.
This test aims to answer a specific question: does this new feature, combined with the already solid system inherited from the previous generation, make the iPhone 18 Pro Max a relevant choice for underwater photography in natural light?
| Overall AquaExposure Score: 4.1/5 | Criterion | Score | What it means |
|---|---|---|---|
| Optics & Sensor | 3.6/5 | Innovative variable aperture, but the physical sensor size remains unchanged. | |
| RAW & Color | 4.7/5 | ProRes RAW video, 12-bit ProRAW, native Blackmagic Camera support, all retained. | |
| Storage & Transfer | 4.3/5 | Up to 2 TB, USB-C USB 3 at 10 Gb/s, no external slot. | |
| Thermal Performance | 2.8/5 | A critical issue remains the same: aluminum + vapor chamber = condensation in the form of cold water. | |
| Battery | 4.0/5 | 5391 to 5567 mAh, a slight improvement, comfortable for a day of three dives. | |
| Autofocus | 5.0/5 | LiDAR + dual pixel PDAF + AI + Focus Peaking via Blackmagic Camera. | |
| Housing | 5.0/5 | Divevolk SeaTouch 6 Pro confirmed, 60 m depth rating, full touchscreen access. |
This device is designed for: underwater photographers who want real creative control over depth of field, in a lightweight configuration with a proven professional video workflow.
This device is not ideal for: regular divers in cold water (below 15 degrees Celsius), for the same reason as the previous generation, condensation related to the aluminum chassis.
Score: 3.6/5The iPhone 18 Pro Max features three 48-megapixel lenses, with a significant innovation in the main lens: a variable aperture ranging from f/1.48 to f/4.0, controllable through the new "Pro controls" in the Camera app, with a histogram and manual settings.
For more details - Main (Fusion): 48 MP, variable aperture f/1.48 to f/4.0, 24 mm, 1/1.28" sensor, 2nd generation sensor-shift stabilization, 100% Focus Pixels. - Ultrawide (UWA): 48 MP, f/2.2, 13 mm, 120 degrees, 48MP macro available (estimated distance close to 2 cm, based on the unchanged ultrawide lens of the previous generation, not precisely documented by Apple). - Telephoto: 48 MP, f/2.8, 100 mm (4x optical), 8x zoom via crop at 12 MP to 200 mm, tetraprism design, 3D sensor-shift stabilization.
The main sensor remains at the 1/1.28" format, the same physical size as the previous generation. The variable aperture doesn't change the scoring on this specific criterion, but it offers real creative control over depth of field that the iPhone 17 Pro Max lacked.
Maximum clean ISO is not officially published by Apple. Estimated to be at least ISO 3200 based on the previous generation. Burst RAW, buffer, and shutter lag are not officially documented. A conservative score of 3/5 is applied to these three criteria, in accordance with the scoring method of the comparison tool.The variable aperture is the most significant feature of this generation. By opening to f/1.48, you gain brightness in low visibility conditions. By closing to f/4.0, you gain depth of field for scenes where you want both the subject and the background to be sharp, a common scenario in underwater photography of sites or schools of fish.
Backlighting on the surface has not been tested in real-world conditions at the time of this publication. The Ceramic Shield 2 and the sapphire crystal of the camera module should limit flare, continuing the trend of the previous generation.
Score: 4.7/5
In this area, the iPhone 18 Pro Max makes no changes, and that's good news: the professional workflow introduced on the iPhone 17 Pro Max is carried over exactly.
Native ProRes RAW video remains available through the Blackmagic Camera app (iOS, free), with Apple Log 2, Genlock, and a manually lockable white balance in Kelvin. In photo mode, ProRAW in DNG 12-bit is native within the Camera app, with the option to choose between 12 MP and 48 MP depending on the need for cropping in post-production.For Further Information
To understand the importance of RAW format in underwater photography, the article RAW vs JPEG: why it changes everything underwater details the principle.
Score: 4.3/5
The configuration is identical to the previous generation: up to 2 TB of internal NVMe storage, without an external card slot, and a USB-C USB 3 port at 10 Gb/s that allows you to offload files to an external SSD directly on the boat, between dives.
For Further Information
Score: 2.8/5
It has the same chassis and the same problem as the iPhone 17 Pro Max, and it's important to state this clearly before any purchase intended for regular underwater use.
The iPhone 18 Pro Max retains the forged aluminum chassis, along with a new-generation vapor chamber, which is three times larger in surface area than the one in the iPhone 17 Pro. In normal use, this configuration dissipates heat very well. However, when used in a waterproof housing in cold water, the effect is the opposite: the aluminum transfers cold to the trapped air, which then condenses on the internal surfaces of the housing.
In tropical waters (above 25 degrees Celsius), the thermal differential remains low, and the risk is limited. In cold water (Atlantic, Mediterranean in winter, mountain lake), the risk of condensation is real, for the same reasons documented in the previous generation.
[!WARNING] Silica gel: mandatory. A packet of silica gel in the housing before each dive remains non-negotiable with this iPhone. The thermal profile (aluminum + vapor chamber) has not changed since the iPhone 17 Pro Max.For More Details
The article Overheating and Condensation of Smartphones Underwater: The Physics of the Housing details the thermal mechanisms and the silica gel protocol.
Score: 4.0/5
The battery capacity increases to 5391 mAh on the Nano-SIM model or 5567 mAh on the eSIM model (the most common in Europe), a slight increase compared to the 5088 mAh of the iPhone 17 Pro Max. Combined with the A20 Pro chip, manufactured using a 2 nm process, power consumption continues to improve.
A full day of three 45-minute dives, with mixed photo and video usage, can be comfortably managed without recharging. When using ProRes RAW on each dive, it is still recommended to have an external 10,000 mAh power bank for liveaboards.For More Information
Before each dive, remember to check your external battery pack. Use our portable battery comparator tool to choose the power bank that is suitable for your underwater housing and your desired dive time.
Score: 5.0/5
The iPhone 18 Pro Max maintains the most comprehensive autofocus configuration available on a smartphone: LiDAR for physical distance measurement (including in turbid water), dual-pixel PDAF on 100% of the pixels of the main sensor, subject tracking via the Photonic Engine, and native Focus Peaking in the Blackmagic Camera app for fine manual focusing.
There are no indications of any regression in this area compared to the iPhone 17 Pro Max. Apple does not communicate any hardware changes to the autofocus system in its 2026 technical specifications.## B7 - The Housing: Divevolk Confirmed Compatibility Upon Release
Score: 5.0/5
DiveVolk confirmed the compatibility of the SeaTouch 6 Pro with the entire iPhone 18 series in a press release dated September 24, 2026, just six days after the phone's release. The internal bay, expanded to 18 mm, easily accommodates the camera module of the iPhone 18 Pro Max. The housing still provides full touchscreen access, including the ability to control the Blackmagic Camera app, and is certified waterproof to 60 meters.
Practical point to note: The SeaTouch 6 Pro is currently available for pre-order at the time of this review, with shipping scheduled for October 15, 2026. Therefore, it is not yet a product that can be physically obtained today, even though compatibility is confirmed on paper.
Available Housing: Divevolk SeaTouch 6 Pro, 18 mm internal bay, waterproof to 60 m, full touchscreen access, pre-order price of €250, shipping scheduled for October 15, 2026.
Field Workflow: A day of 3 dives shooting in ProRAW format generates 20 to 40 GB of data, which can be managed without needing to empty the memory card if you have 512 GB of storage.
Points to Note: Condensation in cold water (a silica gel packet is mandatory below 15°C), no external memory card slot, the SeaTouch 6 Pro has not yet been delivered as of the date of this publication.Observed Prices: Starting from €1599 to €1699 (for the 256GB model) according to European retailers, up to €2399 for the 1TB version (data collected on 2026-09-28, sources: Euronics, Multitronic, GSMArena. These are new prices, and no used devices have been documented so far, as the device has just been released).
Used Market Outlook: Too recent for a structured used market. Keep an eye out in the coming months for divers who want to dedicate an iPhone Pro Max exclusively to underwater use.
The iPhone 18 Pro Max doesn't reinvent anything, and that's almost a compliment. The ProRes RAW workflow and the Blackmagic Camera feature that were strengths of the iPhone 17 Pro Max are fully retained, and there's also a variable aperture that provides a real creative advantage in controlling depth of field. For those who already own an iPhone 17 Pro Max, the upgrade isn't urgent for underwater use alone. For those who are changing phones this year, it's a solid choice, with the same caveat as before regarding condensation in cold water, which should be addressed seriously with a silica gel protocol.
Framing techniques and understanding animal behavior are always more important than the equipment. This is what we teach in the AquaExposure underwater photography course.To compare this model with other smartphones that we have already reviewed, visit our underwater photography equipment comparison tool. And to check the dimensions of compatible underwater housings, use our smartphone waterproof housing comparison tool.
Yes, with an AquaExposure score of 4.1/5, it remains in the top tier of smartphones for underwater photography in natural light. The main improvement in this generation is the variable aperture (f/1.48 to f/4.0), which provides real creative control over depth of field. The main limitation, like in previous generations, remains the potential for condensation in cold water, below 15 degrees Celsius, due to the aluminum frame and the vapor chamber.
The Divevolk SeaTouch 6 Pro, confirmed to be compatible since its announcement on September 24, 2026, features an expanded internal bay of 18 mm to accommodate the thickest camera housings. Certified to a depth of 60 meters, it maintains full touchscreen access. It is still available for pre-order at the time of this review, with a shipping date announced for October 15, 2026.
Yes. The camera captures ProRAW photos in DNG 12-bit format (12 MP or 48 MP, selectable in the Camera app), and records ProRes RAW video via the Blackmagic Camera app, with Apple Log 2 and Genlock support. This is the same professional workflow as found on the iPhone 17 Pro Max, and it's been faithfully replicated in this generation.
With a 5391 mAh battery (Nano-SIM model) or a 5567 mAh battery (eSIM model), and the A20 Pro chip manufactured using a 2nm process, the battery life has improved slightly compared to the iPhone 17 Pro Max. You can comfortably complete a day of diving with three dives, including both photo and video, without needing to recharge. If you are using ProRes RAW on every dive, consider bringing an external 10,000 mAh power bank for liveaboard trips.
The main change is the variable aperture of the main sensor (from f/1.48 to f/4.0), a first for the iPhone, which provides real control over depth of field. New "Pro controls" are available, including a histogram and manual settings. The rest of the camera system (RAW format, storage, thermal management, and autofocus) is almost identical to the previous generation.
Yes, absolutely, and for the same reasons as with the iPhone 17 Pro Max. The aluminum frame and the vapor chamber (even larger in this generation) provide excellent heat dissipation on the surface, but create an unfavorable condensation profile in cold water. A silica gel packet inside the housing remains essential before every dive below 15°C.
The USB-C port, supporting USB 3 speeds up to 10 Gb/s, allows you to transfer RAW files and videos to an external SSD between dives, directly on the boat, without needing a computer. The internal storage capacity reaches up to 2 TB in this generation.